电子束CT气管、支气管树三维重建的评价

目的：评价电子束CT（EBCT）肺扫描图像的三维重建效果及影响因素。材料和方法：研究对象80例，均接受EBCT扫描。扫描条件：130kV/630mA,层厚／间隔分别有6mm/6mm,3mm/3mm,3mm/1.5mm和1.5mm/1.5mm等不同的扫描组合；扫描方式：连续容积扫描（CVS）。其横断面图像转入Insight工作站进行三维重建，重建方式为遮盖表面显示法（shaded surface display,SSD)。重建阈值为－500Hu－-300Hu。结果：3mm层厚／间隔连续容积扫描的三维重建图像可良好地显示部分段及以上的支气管、气管。3mm/3mm层厚／间隔和1.5mm/1.5mm层厚／间隔扫描组的左主、左上叶、左尖后段支气管三维重建图像的评分间均无显著差异，而其积分均高于6mm/6mm层厚／间隔扫描组，有统计学意义。结论：EBCT气管、支气管树三维重建可良好地显示气管以及部分段和段以上的支气管；3mm层厚／间隔连续容积扫描是EBCT气管、支气管树三维重建临床最适合的扫描参数。

Evaluation of Electron Beam Computed Tomography in Three-dimensional Reconstruction of Tracheobronchial Tree

Purpose:To evaluate the imaging effect and influence factor of 3D reconstruction in tracheobronchial tree with EBCT.Materials and Methods:Total 80 cases were scanned with EBCT.All the objects got EBCT examination with thin-sectional scan.The cross-section images were transmitted to the INSIGHT workstation and reconstructed with SSD(Shaded Surface Display),their threshold setting were -500Hu to -300Hu.Results:3D images of 3mm slice thickness/slice interval continuous volume scanning could reveal some segmental and above bronchi?trachea very well.The evaluation scores of left main stem?left upper lobe and left apex-posterior segmental 3D images were of no difference between 3mm/3mm and 1.5mm/1.5mm scanning parameter group,but their scores were all higher than that of 3D images of 6mm/6mm scanning group with statistic significance.Conclusion:3D reconstruction of TBT can demonstrate trachea and bronchus to the third branches.Continuous volume scanning with 3mm slice thickness is the most satisfactory scanning parameter in EBCT 3D reconstruction of TBT clinically.